IMBIV   05474
INSTITUTO MULTIDISCIPLINARIO DE BIOLOGIA VEGETAL
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Reduction of cytotoxicity of ciprofloxacin and production/release of shiga toxin by fruit extracts.
Autor/es:
PELLARIN G; ROJAS MJ ; ALBRECHT C; BECERRA MC; AGUILAR JJ ; ALBESA I; ERASO AJ
Lugar:
Rosario
Reunión:
Congreso; RICiFa 2° Reunión Internacional de Ciencias Farmacéuticas.; 2012
Institución organizadora:
Fac. Ciencias Químicas-UNC y la Univ. Nac. de Rosario
Resumen:
REDUCTION OF CYTOTOXICITY OF CIPROFLOXACIN ANDPRODUCTION/RELEASE OF SHIGA TOXIN BY FRUIT EXTRACTS.
Pellarin G (1), Rojas MJ (1),
Albrecht C (1), Becerra MC (2), Aguilar
JJ (3), Albesa I (2), Eraso AJ (1).
(1) Escuela de
Nutrición, Facultad de Ciencias Médicas, UNC. (2)Dpto. Farmacia,Facultad de Ciencias Químicas, UNC. Ciudad Universitaria, IMBIV-CONICET. (3) Instituto
de Virología, Facultad de Ciencias Médicas, UNC. 5000, Córdoba. República Argentina.
Introduction: Plants useful
for inhibiting the growth of Escherichia coli strainsproducing Stx toxins(STEC) that cause uremic hemolytic syndrome (UHS) have
been reported, including TJ Kim et al. (1), which found antimicrobial activity in grape seed extracts rich
in phenolic compounds. Voravuthikunchaiet al (2) achievedantimicrobial effects and inhibition of toxin
production with extracts of Pomegranate
(Punica granatum) and Quercus infectoria (oak variety). These extracts inhibited the release of Shiga toxins Stx1and Stx2, as well
as reducing the toxic effecton Vero cells.
The aim of this study was to investigate whether the therapeutic
administration of Ziziphus mistol or Prosopis alba extracts with ciprofloxacin
(CIP) could interfere the productionor release of Stx caused by the antibiotic and reduce the cytotoxicity.
Materials and methods: The Minimum Inhibitory
Concentration (MIC) was
determined for CIP, alcoholic and ketonic extracts of Z.mistol or P.alba, and the combination of CIPand extracts. Overnight cultures of E. coli O157: H7 EDL 933 in cysteine trypticase soy medium supplemented
with 0.3% yeast extract, according to Clinical and Laboratory Standards Institute (CLSI) was employed.
Cytotoxicity assays of supernatants from culture free of bacterial cells were
carried out on subconfluent monolayersof Vero cells.
Data were obtained at least in
triplicate and statistically analyzed by ANOVA, consideringp<0.05 as a significant difference.
InfoStat Statistical software was used.
Results: The MIC of the antibioticwas 0.039 µg/ml and none of the extracts showedantimicrobial activity at the concentrations tested. In addition, it was found that alcoholic and ketonic extracts of P.albaand the ketone extract of Z.mistol
did not change the MIC of the antibiotic. However, a slight increase (1dilution) of the MICwith the alcoholic extract of Z.mistol was detected.
Moreover, CIP favored the production/release of toxin in the assays in
which the bacterium was exposed
to sublethal doses of the
antibiotic. By cultivating thebacterium with a
combination of Stx and extract, it was observed that the alcoholic extracts of both fruits wereprotectors for Vero cells, with significant
decreases in toxicity found in cultures
treated only with CIP. The percentages ofreduction of the
cytotoxicity of Stx were 70% and 60%,respectively for Z.mistol and P.alba. Notably,it was found that the plant extracts
reduced the Stx damage on the Vero cellswhen they were previously incubated with
the toxin for 1 h.
Discussion: The protective effect of the
extracts on the Vero cell line coupled with the significant decrease in the
production/release of Stx are two beneficial effects that could prove useful
for developing a complementary treatment of antibiotic therapy, especially if
we consider that various antibiotics in addition to CIP, are capable of generating
oxidative stress damage in different eucaryotic cells. Conclusion: This study shows that the extracts of both regional
fruits may have a preventive role or as part of palliative strategy against UHS, either as potential pharmacological
applications or as diet therapy to reduce long-term consequences of this
infectious disease.
References:
(1)-Kim TJ, Silva JL, Jung
YS. Antibacterial
activity of fresh and processed red muscadine juice and the role of their
polar compounds on Escherichia coli O157:H7. J Appl Microbiol. 2009,
107:533-9.
(2)-Voravuthikunchai SP,
Limsuwan S. Medicinal
plant extracts as anti-Escherichia coli O157:H7
agents and their effects on bacterial cell aggregation. J Food Prot. 2006.69:2336-41.
Alberto Eraso. Escuela de Nutrición. Facultad de
Ciencias Médicas. UNC. aeraso@fcm.unc.edu.ar
TE-FAX: 4333024 int 102.